This invention relates to a mechanism for rotating a hollow cylindrical article, such as a coil of continuous sheet material, for example, about its longitudinal axis.
In the manufacture of continuous lengths of material, such as metal sheet, for example, the material is typically wound in a coil during the course of manufacture. Thereafter, it may be necessary to unwind at least a portion of the coil for such reasons as removal of one or more outer layers because of material defects or to check the quality of material within the coil underlying one or more of the outer layers. One mechanism which has been used heretofore for accomplishing such unwinding has been an upright pedestal having a freely rotating or power-driven mandrel cantilevered outwardly therefrom. The mandrel is adapted to engage a coil mounted thereon with a sufficient degree of tightness that the coil is rotated coincident with rotation of the mandrel. Another mechanism that has been used for unwinding coiled material is termed a "saddle". A saddle is comprised of spaced apart rollers having parallel axes of rotation which may be mounted on the floor or a supporting frame. The spacing of the rollers is such that they serve to support a coil that is placed upon them with the coil axis parallel to and centered between the roller axes. The rollers may be power driven to rotate the coil from frictional contact between the coil and the rollers or, if the rollers are free to rotate, material may be pulled from the coil and the roller supported coil is thereby rotated. Heretofore, if it were desired to unwind a coil, it has been necessary to transport the coil to such a just-described device. In many instances, such a transport unduly disrupts the normal processing of the material since the coil has to be moved from a work station to the rotate device, mounted thereon for unwinding and then transported back to the work station.
It would be desirable, therefore, to provide a mechanism for rotating a coil of material about its longitudinal axis which may be transported to the coil location and thereby minimize the time required to unwind the coil.